Bacteremia caused by antimicrobial resistant Campylobacter species at a medical center in Taiwan, 1998–2008

Abstract

This study was intended to delineate the clinical and microbiological characteristics of patients with bacteremia caused by Campylobacter species. Twenty-four patients with Campylobacter bacteremia were treated at the National Taiwan University Hospital from 1998 to 2008. All isolates from the 24 patients were confirmed to the species level by multiplex PCR (cadF, hipO and asp gene) and 16S RNA gene sequencing. Bacteremia was caused by Campylobacter coli in 15 (62.5%) patients, Campylobacter fetus in 6 (25%), and Campylobacter jejuni in 3 (12.5%). Of the 24 patients, 16 were male. The major underlying conditions included chronic renal insufficiency (41.7%), liver cirrhosis (37.5%), malignancy (33.3%), and previous abdominal surgery (33.3%). The most common infections were intra-abdominal infection (54.2%), followed by primary bacteremia (41.7%), and cellulitis (4.2%). The mean Pittsburgh bacteremia score was 2.5 (range, 0-9). During the bacteremic episodes, six (25%) patients developed septic shock. Third-generation cephalosporins were administered to 12 (50%) patients as empirical therapy. All-cause mortality was 4.2% at 14 days and 12.5% at 30 days. The majority of the isolates were resistant to third-generation cephalosporins and quinolones, with minimum inhibitory concentration (MIC(90)) values of 32 mg/L for cefotaxime, 128 mg/L for ceftriaxone, and 32 mg/L for both ciprofloxacin and levofloxacin. All isolates possessed a parC mutation (Arg-139-Gln) and 15 exhibited an additional gyrA mutation (Thr-86-Ile). Among these isolates, 20.8% were susceptible to erythromycin (MIC≤0.5 mg/L). Bacteremia caused by antimicrobial resistant Campylobacter species is alarming although the mortality rate is low.